Graduate student honored for desert tortoise research

A University of Florida pathobiology graduate student won the award for best paper presented by a student at this year’s 26th Annual Desert Tortoise Council Meeting and Symposium.

Lisa Domico, who competed with students from other schools across the U.S., was honored for her research involving the isolation of a metal-binding protein from the liver of the desert tortoise. “We were looking to do a project that would pinpoint or help to pinpoint some of the problems with the desert tortoise,” Domico said of her work.

Under the tutelage of her advisor, pathobiology professor Bruce L. Homer, D.V.M., Ph.D., Domico worked to develop a test to identify toxic heavy metal exposure in the desert tortoise. When an animal is exposed to heavy metals, a protein in the liver, called metallothionein, is induced and the concentration of the protein will elevate.

“We were hoping to isolate this protein from the desert tortoise liver, characterize it and eventually develop an assay to test other desert tortoises to see if this protein has been induced in them as well,” Domico said. “There’s been a decrease in some populations of the desert tortoise, and we think there might be a correlation between disease and heavy metal exposure.”

The desert tortoise is listed as a threatened species in California. It can be exposed to toxic heavy metals found naturally in the earth or released by human activities such as mining, industrial waste and fossil fuel combustion.

Both are non-degradable and contaminate the desert tortoise’s environment.

“The desert tortoise can incidentally ingest sediment, plants and water. All these things would expose the tortoise to heavy metals,” Domico said.

Heavy metal exposure can cause liver and kidney damage in the desert tortoise, as well as a weakened immune system, upper respitory tract disease, shell disease and other maladies.

She added that she hoped her research might provide an indication of whether there is a level of heavy metal exposure in desert tortoise populations that should be explored further, and might play an important role in disease and pathology research.

“I think its ultimate importance is that it may, great or small, play a part in determining why the desert tortoise population is threatened in California, and may shed light on the cause of some of these diseases that are killing the desert tortoises,” Domico said.

Baltimore-born Domico, 25, has been seeking her master’s degree as a UF veterinary college graduate student since she graduated from Chestnut Hill College in Philadelphia with a degree in biology and environmental science. After she finishes her program in August, Domico will enter the Ph.D. toxicology program at Rutgers University, where she hopes to focus on wildlife and environmental toxicology issues.

This was Domico’s first time attending the Desert Tortoise Council, which is an annual scientific meeting devoted to the status, management, recovery, health, ecology, physiology and nutrition of free-ranging desert tortoises.

Domico, who was awarded $150 in prize money, said her research is of special interest to toxicologists, wildlife management and government agencies interested in protecting threatened or endangered species.

“Any animal, any species, even humans, are at risk for heavy metal exposure when its present,” Domico said. “This is the beginning stage of a project that may eventually be able to pinpoint heavy metal exposure.”

Funding for Domico’s research came from the United States Geological Survey, the Fort Irwin National Training Center and the UF College of Veterinary Medicine.